Devices for delivery of aerosolized drug substances, including delivery via inhalation, are known in the art, examples including U.S. Pat. Nos. 5,694,920, 6,026,809, 6,142,146, all by Abrams and Gumaste, U.S. Pat. No. 3,948,264 by Wilke et al., U.S. Pat. No. 6,971,383 by Hickey et al., U.S. Pat. No. 7,117,867 by Cox et al., U.S. Pat. No. 6,901,929 by Burr et al., U.S. Pat. No. 6,779,520 by Genova et al., U.S. Pat. No. 6,748,944 by DellaVecchia et al., U.S. Pat. No. 5,590,645 by Davies et al. The above patents also provide an overview of various aerosolization and inhalation devices and techniques.
A range of aerosolization and inhalation drug delivery devices is known, including metered dose inhalers, nebulizers, dry powder inhalers, thermal vaporizers, and other systems, with differences related to methods and efficiency of aerosolization and delivery of drug substances to the patient. Metered dose inhalers are typically using pressurized gas to aerosolize the drug substance. Disadvantages of these inhalers are related to difficulties to control the delivered dose of the drug substance and also to high speed of aerosol particles, resulting in particles impinging and depositing on various surfaces in the mouth and in the throat of a patient. Inhalation devices delivering drug substances as a dry powder are known as dry powder inhalers. Passive dry powder inhalers rely on the patient's inspiratory effort to de-aggregate and aerosolize drug substance for inhalation, while active dry powder inhalers typically input additional energy, such as mechanical or electrical energy in order to improve the efficiency of powder deaggregation and aerosolization, to decrease the inspiratory effort needed from the patient, and to achieve better inspiratory flow independence of the inhaler performance. Typically for delivery of drug substances to the lungs of a patient via inhalation, the drug aerosol particle size has to be less than about 10 microns, more preferably less than about 6 microns, and for delivery to deep lung less than about 3.3 microns. Larger size particles will be delivered to the mouth and throat of the patient and as a result will be delivered to the gastrointestinal tract of the patient. There is a need to increase the quantities of a drug that dry powder inhalers are capable of aerosolizing during a single inhalation by a patient, e.g. within one to three-four seconds. There is also a need to increase the speed of deaggregation and aerosolization of powders by dry powder inhalers.
Dry powder inhalation devices described in U.S. Pat. Nos. 5,694,920, 6,026,809, 6,142,146, all by Abrams and Gumaste, utilize vibratory means to deaggregate and aerosolize dry powder medication for delivery to the patient as an aerosol. US Patent Publication 2005/0183724 by Gumaste and Bowers discloses a synthetic jet-based medicament delivery method and apparatus.